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There is also throttle body cleaner which is supposed to contain less of the chemicals that can foul sensors. Your call whether to use that or carb cleaner.

I've never quoted myself before. But that was my understanding. Carb cleaner .. not good for the advanced sensors in our engines. I also heard somewhere that it can deteriorate the plastics over time (lots of plastic in/around our engine)

You might want to try seafoam in a vacuum hose (?). It will make your car smoke lke crazy for 5 minutes but its supposed to emulsify/liquify all the nasty carbon and help it get out the engine. Maybe it can get out some of the chemicals that are causing you problems (if thats the reason) I've used it in injected cars before (ford modular V8 in two different cars) and it definitely didnt hurt anything.

Seafoam is the greatest stuff!!!! I use to work at a car shop and I would charge people $30 to do the fuel injection cleaning with Seafoam, everyone loved the results. Last time I cleaned the system was with B&G fuel injection cleaner(through the IVY bottle).

I think what I'm going to do is re-do the ICV cleaning with throttle body cleaner.

Another thing, when I pulled the DISA out it had some gunk on it that I cleaned with that carb cleaner. What does the DISA do?

If the redo cleaning doesn't work I will have no choice but to seafoam the car and flush all that sh*t out of it.

I would never use regular carb cleaner for fuel injected engines... like someone said before, they aren't safe for sensors in our cars. I would never use brake cleaner either personally... stick with a maf/throttle body cleaner, and you should be fine, or seafoam it as that stuff is great.

I have been getting the exact same symptoms on my 5er. Cleaned the ICV (helped a little with the speed of the idle, increased it a little bit, but that's it), changed the O2 sensor, but the problem remains.

The cause as found by my mechanic is a vacuum leak from the throttle body gasket in between the throttle body and the intake control valve, which is a breeze to replace. The part (few bucks) is in order and I will be replacing it this weekend.

Would you be able to tell me hte part # for this intake boot? I assume it's not the often discussed intake 'accordion' boot that leads to the MAF is it?

On the differentiated intake system there is a connecting valve between the intake pipes. This is closed when the engine is turning at low speeds to create high torque due to the long intake distance. When the engine is turning faster the valve opens – to produce a short intake distance and therefore more torque and power.

DISA uses a physical phenomenon – when the length of the intake pipe has been adjusted to the engine speed, a “reboosting effect” is created by the vibrating air column before the inlet valve closes. This optimises the torque in both the lower and the upper engine speed range.

Advantages

Conventional engines have a fixed intake distance, which cannot be altered. However, optimal torque values can only be achieved with a long intake distance at low engine speeds and a short intake distance for a fast turning engine. Optimising this for low engine speeds would therefore result in reduced power in the upper engine speed range.

This is where the DISA comes into it – when the engine is turning slowly it provides a long intake distance and when it is turning faster it switches to the shorter intake distance. This means high torque and high power at all times.

if faulty, it should not cause driveability issues. It would only lower your power. Unless, of course, the gasket for it is letting air leak into the intake unmetered. You should seal it back in with sensor safe RTV to eliminate that problem

Well I found something out the hard way about that #10 gasket that connects to the ICV. Apparently when I installed the ICV after i cleaned it the other day I pushed the gasket half way inside, meaning.........a very bad vacuum leak.

I dam near sh*t my pants when I realized and had pushed it inside the intake manifold. Luckily......some how I was able to get it out with my fingers.

That #10 gasket looks nothing like the picture shows, the one on my car was in a "L" shape.

So I re-cleaned the ICV put everything back together, reset the computer and now......

I used GUNK intake medic throttle body cleaner and it says on the bottle "used to clean idle control valves".
This stuff definitely did the trick and the car runs a lot better at idle, and cleaning the MAF helped a lot as well, i recommend doing both at the same time and your supposed to clean the MAF routinely, like every oil change.

Just make sure when you do this, all the hose clamps and hoses are properly put back and tightened.

If you are starting the car cold and then it just dies, then you start it back up and it runs fine, Fuel Filter is most likely the culprit. I had this on my car, replaced it and problem went away. Other members on here have had similar results. Next time you start it, leave the key in the On position for a few seconds to let the fuel pump run, then start the car. If it no longer stalls look into that.

Edit - just noticed you fixed the prob, nice work.

Lately I have a new bug where occasionally when I start it cold it will hiccup for a moment then run fine. Every time it gets cold something new peeks its head. Could be Vanos related, I've been meaning to do those seals. I'll prolly just change out the fuel pump relay first, last year my Secondary Air Pump really burnt out so it's very possible my fuel pump relay may also be going bad, cheap preventative maintenance if anything else.